Stocks in 2025 show the market's biggest winners and losers.

The S&P 500 rose about 17% in 2025 as enthusiasm for artificial intelligence helped lift technology and data-related firms. Data storage and data-center companies were among the year’s top gainers, while some consumer and health-care stocks lagged amid policy and trade uncertainty.

Stocks in the U.S. market finished 2025 with notable gains concentrated in technology and data-related firms. The S&P 500 was up roughly 17% as a third year of gains continued. Interest in artificial intelligence and related infrastructure helped reshape market leadership. Companies tied to data storage and data-center construction were among the strongest performers. What we know so far: - The S&P 500 gained about 17% for the year, reported as driven largely by technology-related strength. - Data storage firms such as Sandisk, Western Digital and Seagate were among the top performers in the index. - Major cloud providers were reported as planning more than $440 billion in spending to expand AI capacity, benefiting firms that support data centers. - Several companies added to the S&P 500 in 2025 posted large gains, including Robinhood, Sandisk, AppLovin and Carvana. - Some stocks fell sharply; Trade Desk was reported as the poorest S&P 500 performer with a near 70% decline, while Block and Coinbase also posted notable losses. - Consumer and health-care names faced pressure amid reported trade measures and uncertainty over policy direction. Summary: Technology and data-related companies led market gains and helped lift the S&P 500 in 2025. Undetermined at this time.